Many gym sets in use today include a swing whose seat, instead of being a rigid platform, is a flexible strap which, when suspended by chains from the crossbar of the gym set, forms a swing in which the child can sit comfortably. Such a flexible swing seat has an advantage because if a moving seat happens to strike a child, the impact will not cause serious injury to the child. Also, a sling-type seat conforms to the rider's body and tends to retain the rider on the seat. Still further, the seat is usually more comfortable than a rigid platform-type seat.
The usual sling-type swing seat includes a flexible rectangular strap having a pair of inextensible, flexible connector members, such as metal strips or chains captured by the strap adjacent to the front and rear edges thereof and extending the full length of the strap. A pair of rigid wire hangers are anchored to corresponding ends of those members at opposite ends of the strap. The hangers have end hooks which hook through eyes or links at the ends of the connector members. The hangers are then suspended by chains from an overhead cross bar or other support to position the seat above the ground. For this, the links at the upper ends of the chains are connected by hooks to bearing assemblies anchored to the overhead support. An example of such a seat is disclosed in U.S. Pat. No. 3,897,056.
Conventional flexible swing seats are disadvantaged, however, in that they still present some danger to children because the connections between the hangers and the inextensible members extending along the strap-like seat are more or less exposed and constitute pinch points which can injure the fingers of a child sitting on the seat. Similar pinch points exist where the upper ends of the chains are connected by S-hooks to the overhead support and these connections are also accessible to a child who happens to swing while standing on the seat.
A somewhat similar seat disclosed in U.S. Pat. No. 4,478,410 avoids the need for separate connector members in the seat and separate wire hangers by routing the seat suspension chains through integral tubes in the seat strap. An S-hook connects the free lower end of each chain to the opposite chain just above the seat so that the chains themselves form the seat hangers. In this type of seat, pinch points are located at the S-hooks which connect the chains together just above the seat.
Another problem with swings of this type as well as with swings in general which use hooks as connectors, stems from the fact that the hooks are not always closed completely about the chain link, ring or other eye-forming member to which they are connected. Accordingly, when the swing is in motion, an unclosed hook can disengage accidently from the eye-forming member causing one side of the swing to collapse. Obviously such collapse can cause serious injury to the child swinging on the swing. Swing failure due to incomplete closure of connector hooks is particularly prevalent in the case of swing sets assembled by the customers because the customers frequently fail to follow the instructions accompanying the swing sets.